Omron NJ501 - IFM IO-Link - Wenglor U1KT001

[andrei.apopei 0]

Hi,

I am looking at reading an ultrasonic sensor value through IO-Link, using a Omron NJ501-1320 PLC connected through EtherCat to a IFM AL1332 master with a Wenglor U1KT001 Ultrasonic sensor.

I have managed to read the 2 outputs of the sensor using this:

Output_1 := TestABit(USINT_TO_BYTE(TxPDO_input_byte_1_6000_02),USINT#0);

Output_2 := TestABit(USINT_TO_BYTE(TxPDO_input_byte_1_6000_02),USINT#1);

But cannot read the ultrasonic sensor distance value, this is what page 2 in the manual says:

Measured Value in 1/10 mm 2…15 14 Bit 300…4500

Octet 1 Subindex 3 (LSB) 2 1 Bit Offset 7 6 5 4 3 2 1 0

I tried a couple of conversions but couldn`t get the distance reading.

Any ideas?

Help appreciated.

Edited 27 Nov 2020 by andrei.apopei

[chelton 42]

Have you tried moving the 2 bytes into a Word data type then shifting the bits 2 places to the right with a SHR ?

Edited 27 Nov 2020 by chelton
Wrong direction

[andrei.apopei 0]

Not sure I understand, the measured distance is 14 Bit, do you mean move them into a bit array?

I have tried moving them into a bit array and then using AryByteTo  into a Real number but it doesn`t really work because I can`t choose the array offset.

TempByteArray[2] := USINT_TO_BYTE( TxPDO_input_byte_1_6000_02);
TempByteArray[3] := USINT_TO_BYTE( TxPDO_input_byte_1_6000_02);
TempByteArray[0] := USINT_TO_BYTE( TxPDO_input_byte_1_6000_02);
TempByteArray[1] := USINT_TO_BYTE( TxPDO_input_byte_1_6000_02);
AryByteTo(In:=TempByteArray2[0], Size:=4, Order:=_HIGH_LOW, OutVal:=Ultrasonic_Measurement);

[chelton 42]

Create a temp "WORD" variable

use AryByteTo to move the 2 bytes into your WORD variable.

shift the word bits to the right x 2 bits.

 

AryByteTo(byte_Array[4],UINT#2,_LOW_HIGH,tempword);
distance:= to_uint(SHR(tempword,UINT#2));

 

[chelton 42]

Since your bytes aren't in an array you will use the packword function....

tempword := packword(TxPDO_input_byte_1_6000_02,TxPDO_input_byte_1_6000_03);
distance:= to_uint(SHR(tempword,UINT#2));

 

[andrei.apopei 0]

Hi Chelton and thanks for replying.

I gave it a try with the second one and with a couple of mods I get the output in the picture, it is about half of the real measurement.

 

 

[chelton 42]

Hi Andrei, Are you sure your not supposed to be using Tx_PDO_InputByte 0 & 1? Your link is showing input byte 1&2

Byte 1 will contain the digital status like you have shown, but I think the MSB byte should be byte 0

 

[andrei.apopei 0]

Hi Chelton, you are right, I was using the wrong ones:

https://ibb.co/jgc7PM3

https://ibb.co/bbB3zqp

Thank you very much for your help!

Edited 1 Dec 2020 by andrei.apopei

[chelton 42]

No problem.